Credentials side by side: how each one is assessed, and for how long
Written exam, skills test, portfolio or practical, with the question counts, time limits and pass marks the bodies publish. ISA, TCIA, the Arboricultural Association, Arboriculture Australia, NZ Arb, the European Arboricultural Council and the UK awarding bodies, in one place.
Checked against the sources at the bottom of this page on October 8, 2026. Rules, fees and pay change: the source has the last word.
This page sets out how each body says its credential is assessed. It lists, it does not rank, and it does not teach any exam content. Bodies assess in very different ways: some run a knowledge exam, some add a skills test, and some grade membership or a business by portfolio and visit. An empty cell reads "Not published" where the body's page, read on October 8, 2026, gives no answer. The companion tables cover who may sit or apply and renewal, CEUs, CPD and fees. ISA's program guides say its credentials do not represent licensure or authorization to practice.
ISA written exams
Every ISA guide read says the questions are multiple choice with one correct answer, that a set number of unscored new questions is mixed in without being marked, and that the passing score can change when the exam is reviewed. Where a guide counts the unscored questions inside the total or beside it, the cell says what the guide says.
| Credential | Format and time | Passing score |
|---|---|---|
| Certified Arborist | Written: 200 questions, with 20 new unscored questions within the exam; 3.5 hours (210 minutes); ten knowledge areas. | 76 percent |
| Certified Tree Climber | Written: 65 questions, with 15 new unscored questions within the exam; 1.5 hours (90 minutes). Practical: Outdoor practicum with 45 minutes for the climb, judged by at least two trained evaluators. | 80 percent written; 70 percent skills, with at least 27 points and no critical task failed |
| Certified Arborist Utility Specialist | Written: 115 questions, with 15 new unscored questions within the exam; two hours (120 minutes). | 75 percent |
| Certified Urban Forest Professional | Written: 115 questions, with 15 new unscored questions within the exam; two hours (120 minutes). | 70 percent |
| Board Certified Master Arborist | Written: 165 questions, with 15 new unscored questions within the exam; each has three or four answer choices; four hours (240 minutes); 17 knowledge areas. | 70 percent |
| Tree Risk Assessment Qualification | Written: 110 questions with four answer choices; two hours. The guide separately mentions 10 new unscored questions. Practical: Outdoor assessment of a tree at the training site; one hour. | 75 percent written; a passing mark on the performance part |
The Climber guide says a participant in an ISA chapter, associate organization, regional or International Tree Climbing Championship may waive the skills part, provided the other requirements and the Skills Exam Waiver Form are met. ISA says Pearson VUE grades computer-based exams and ISA headquarters grades paper and skills events.
All other bodies
| Credential | How it is assessed, as the body states it |
|---|---|
| TCIA Certified Treecare Safety Professional | After a workshop, an online proctored exam. Candidates have five days to finish, counting from the day after the workshop. Retakes are allowed twice within 12 months of enrollment. The ANSI Z133 standard may be used during the exam. Question count and pass mark: Not published on the pages read. |
| Arboricultural Association, Technician, Professional and Fellow | Graded by membership application against a qualification level. No exam on the grade pages read. Question count and time: Not published. |
| Arboricultural Association, Registered Consultant | A portfolio of reports and supporting information, then an interview with the assessors if the portfolio succeeds, with submission dates of March 1 and September 1 each year. |
| City and Guilds (formerly NPTC) and Lantra Awards | UK FISA's guide 805 says competence can be confirmed by an assessment built into training, or by an independent assessment leading to a recognised qualification. Question counts and times: Not published on the pages read. |
| Arboriculture Australia, Registered Members | Approval by the body against listed qualifications and insurance. No exam on the page read. Time and format of any assessment: Not published. |
| NZ Arb, Registered Master Arborists NZ | A business portfolio is reviewed first, in a two-week pre-assessment period. An assessor then visits for an on-site assessment of work examples and systems, with a mid-term audit in the third year. No written exam in the application guide. |
European Tree Worker and Technician
The European Arboricultural Council (EAC) publishes the exam parts in its rules, which cover the European Tree Worker (ETW) in the January 2021 version, and on its Technician page.
| Credential and part | Format and time | Pass rate |
|---|---|---|
| ETW, written theory | 30 multiple choice questions with four answers, plus 8 open questions on national rules; 60 minutes | 50 percent of points in each part |
| ETW, oral | 15 to 20 minutes with two examiners | 50 percent |
| ETW, tree identification | 15 species samples in 15 minutes at most, written answers | 67 percent (30 of 45 points) |
| ETW, practical climbing or platform | 60 minutes of crown pruning, at most 30 of them to reach the first working position; trees at least 15 meters tall | 50 percent |
| ETW, ground worker | 60 minutes as a team with the climber or platform operator, plus a 15 minute oral part | 50 percent |
| ETW, simulations 1 and 2 | 20 to 30 minutes each, from listed subjects such as young tree pruning, planting, basic inspection and felling and rigging | 50 percent each |
| ETW, simulation 3 (aerial rescue) | Optional; used where no formal aerial rescue certification exists in the candidate's country | 50 percent |
| ETT, written | Half short questions (about 60 minutes) and half essay questions (about 120 minutes); no longer than 180 minutes | Not published on the page read |
| ETT, tree inspection exercise | A tree survey and a detailed inspection of one tree, with oral questions; up to 60 minutes | Not published on the page read |
| ETT, economics, law and social studies exercise | Management exercise with oral questions; up to 180 minutes | Not published on the page read |
The EAC rules also say a candidate may retake individual failed parts twice, no sooner than one month and no later than two years after the first exam. The guide on the European Tree Worker and Technician adds the countries, centres and dates the EAC lists.
Sources
- ISA, Certified Arborist program guide, revised August 2025, read October 8, 2026
- ISA, Certified Tree Climber program guide, revised August 2025, read October 8, 2026
- ISA, Certified Arborist Utility Specialist program guide, revised August 2025, read October 8, 2026
- ISA, Certified Urban Forest Professional program guide, revised August 2025, read October 8, 2026
- ISA, Board Certified Master Arborist program guide, revised May 2026, read October 8, 2026
- ISA, Tree Risk Assessment Qualification application guide, revised July 2026, read October 8, 2026
- TCIA, Certified Treecare Safety Professional, read October 8, 2026
- Arboricultural Association, Become a Registered Consultant, read October 8, 2026
- Arboricultural Association, Technician membership grade, read October 8, 2026
- UK FISA, safety guide 805 Training and certification, update August 2025, read October 8, 2026
- Arboriculture Australia, Join Arboriculture Australia, read October 8, 2026
- NZ Arb, Registered Master Arborists NZ Application Guide, read October 8, 2026
- European Arboricultural Council, European Tree Worker exam rules, version January 2021, read October 8, 2026
- European Arboricultural Council, European Tree Technician, read October 8, 2026